Influence of first proximal phalanx geometry on hallux valgus deformity: a finite element analysis

Abstract

Hallux abducto valgus (HAV), one of the most common forefoot deformities, occurs primarily in elderly women. HAV is a complex disease without a clearly identifiable cause for its higher prevalence in women compared with men. Several studies have reported various skeletal parameters related to HAV. This study examined the geometry of the proximal phalanx of the hallux (PPH) as a potential etiologic factor in this deformity. A total of 43 cadaver feet (22 males and 21 females) were examined by means of cadaveric dissection. From these data, ten representative PPHs for both genders were selected, corresponding to five percentiles for males (0, 25, 50, 75, and 100%) and five for females. These ten different PPHs were modeled and inserted in ten foot models. Stress distribution patterns within these ten PPH models were qualitatively compared using finite element analysis. In the ten cases analyzed, tensile stresses were larger on the lateral side, whereas compressive stresses were larger on the medial side. The bones of males were larger than female bones for each of the parameters examined; however, the mean difference between lateral and medial sides of the PPH (mean ± SD) was larger in women. Also the shallower the concavity at the base of the PPH, the larger the compressive stresses predicted. Internal forces on the PPH, due to differences in length between its medial and lateral sides, may force the PPH into a less-stressful position. The geometry of the PPH is a significant factor in HAV development influencing the other reported skeletal parameters and, thus, should be considered during preoperative evaluation. Clinical assessment should evaluate the first ray as a whole and not as isolated factors.

PREVALENCE OF HALLUX ABDUCTO VALGUS AMONG VARIOUS GROUPS IN ANAMBRA STATE OF NIGERIA; Predominio de hallux abducto valgus entre varios grupos en el estado de anambra de Nigeria

“…It is generally believed that HAV is more prevalent in females than in males (Dare et al, 2005, Morales-Orcajo et al, 2015, Dufour et al, 2014, Nguyen, 2010, Cho et al, 2009), but our study did not support this assertion. However, it is reported that the true sex ratio in the prevalence of HAV is actually unknown (Perera et al, 2011).…”

“…Bunions may also be caused by some other factors which include osteoarthritis, bursal inflammation, ganglion formation or gouty arthropathy. The aetiology of HAV is not clearly identified (Morales-Orcajo et al, 2015). Some of the suspected aetiologic factors include: high-heeled shoe wearing, excessive weight-bearing, genetic factor, race and sexual dimorphism (Perera et al, 2011).…”

“…In Nigeria, Owoeye et al (2011), reported a prevalence of 15.4%, among a youth population in Lagos, while a survey conducted among three ethnic groups in Delta state showed a prevalence of 28%, 25% and 23.3% for Isoko, Urhobo and Delta Ibo respectively (Dare et al, 2005). The literature suggests that HAV is more prevalent in women; a notion which is attributed to use of high heeled shoes in women (Dare et al, 2005, Okuda et al, 2014, Morales-Orcajo et al, 2015, Nguyen, 2010, Mafart, 2007. A study in Boston among elderly subjects reported a prevalence of 58% in women and 25% in men (Nguyen, 2010).…”

Geometry of the Proximal Phalanx of Hallux and First Metatarsal Bone to Predict Hallux Abducto Valgus: A Radiological Study

“…The difference between the medial and lateral aspect of PPH was also calculated [33] (Fig 1). All measurements were performed in an independent blinded fashion.…”

“…Recently, in a cadaveric study [32,33], the dimensions of the proximal phalanx hallux (PPH) in normal feet in both men and women were studied to determinate the height, base width, longitudinal distance of the medial, central and lateral aspect of the proximal phalanx. Significant differences were found between the genders in most dimensions of the PPH, except for the depth of the concave area of the base of the proximal phalanx.…”